Is it possible to walk from Heathrow Terminal 4 to Heathrow Terminal 5?
Heathrow Airport is a vast secure area where pedestrians are very much not welcome, indeed it would be dangerous if they were. It's impossible, for example, to escape Terminals 2 and 3 in the middle of the airport except via some means of transport, which might be car, bus, train or plane. But Terminals 4 and 5 are on the edge, so might it be possible to walk around the perimeter from one to the other? Spoiler: it looked impossible to start with, but actually yes, it is.
Terminal 4 is the least loved of the Heathrow litter, cutting edge when it opened 30 years ago but a little tired now and somewhat out on a limb. It sits on the Southern Perimeter Road, attached via loops of tarmac to the A30, part of as artificial an environment as almost anywhere in London gets. My first task was to exit the tube station and try to find a way outside. Officially you're not supposed to do this - a sign on the first door past the ticket barrier announces that only those with legitimate business in the airport are allowed to enter the terminal building. Stuff that. Ascending to Arrivals on the ground floor there are signs for Taxis, and the Car Park, and the Bus Station, and aha, also a sign for Exit! Alas, this encouraging omen disappears as soon as you step outside. The taxi rank is obvious, as is the dead end multi-storey, and a couple of bus stops down by the smoking area, but the rest looks seriously enclosed. Only if you search past the bus stops does the pedestrian exit become apparent - a wiggling lane painted green between barriers beneath a concrete overpass.
This is not a well-used exit. It leads past barbed wire and a locked spiral staircase to a road junction where connection is made with the outside world. Just not much of a connection if you're a pedestrian. The only pavement heading west, which is the way we need to go, peters out after climbing to a big scary roundabout it'd be inadvisable to cross. A massive Hilton hotel blocks the way to the south, so the only way to go is east, suggesting that the only way to reach T5 might be via an extended anti-clockwise detour. Thankfully an official gap in the fence leads out to the A30, if you can call walking alongside a bleak busy dual carriageway worthy of thanks. And just when it looks like this too is going to be a protracted diversion, a concrete-banked river ducks underneath.
In fact there are two parallel rivers, the Longford and the Duke of Northumberland's, both artificial and both worthy of blogging at far greater length. The Longford delivers water from the River Colne to Hampton Court, while the Duke of Northumberland's is older and once drove watermills near Syon Park. Importantly for the purposes of this journey both had to be diverted when Heathrow was built in 1944, and again for Terminal 5, so now follow the entire southern and western perimeter of the airport. They form an excellent additional security perimeter, with airport traffic within and the real world without, and provide a biodiversity corridor to boot. What's more, the only sensible way for me to make progress to the west was to step down a steep slope to the waterside and follow an unpaved path along the river's edge.
If I was surprised by the low key nature of this westbound connection, I was also surprised how many people were using it. A couple of dogwalkers lingered along the way, allowing their hound to relieve itself on the landscaped embankment, while others dashed through on their way to jobs in and around the airport. If you live in East Bedfont, your nearest tube station (or employment opportunity) is only a dangerous dash across an enormous gyratory system away. At the first bridge across the two rivers an industrial estate intrudes, at which point there's a bus stop, and from which point there's continuous pavement all the way to Terminal 5. Take your pick whether you'd like to walk along the road or the river, with one option a trifle more scenic than the other.
The Southern Perimeter Road is busy, a lot of it with heavy lorries, because this is very much the freight side of the airport. A scalloped concrete wall has been built alongside the first bend to protect the public, or passing traffic, from jet exhaust emissions. A warren of barriered gates lies off the next roundabout, heavily sentried, opposite the animal quarantine station. Gate Gourmet trucks queue up to enter the airport complex at Sealand Road, bringing compacted chicken and/or pasta meals to the departing hordes. Just beyond their HQ, off Southampton Road, rises the metallic swoop of the British Airways Cargo Terminal. Top fact - all the roads along the southern edge of Heathrow Airport have names beginning with S, for compass reasons, with W, N and E used elsewhere around the perimeter, and C in the centre.
You're right, it would be much more pleasant to walk along the rivers instead. Better still you can walk inbetween them - a thin causeway of greenspace permits - cut off from the main road on one side and further trading estates on the other. I disturbed a heron on my way through, and admired the occasional copse of trees, each of a similar height and size as befits a rash of landscaping completed twenty years ago. They've done a good job, considering the bleak anodyne landscape these borderlands could have become. A BP garage heralds the northern edge of the suburb of Stanwell, an ideal place to live for those who work at the airport, hence the occasional stewardess to be seen scuttling across the river and along the main road in pristine get-up. There's even a pub at the top end, an interwar high-gabled affair called The Rising Sun, but that's fractionally across the border in Surrey so need not concern us here.
If you like planes, you'll love the next bit. The main road veers north to nudge closer to the airfield proper, with the rivers crossing underneath to nudge closer still. This means an almost unrestricted view of operations at the western end of the southern runway, with precisely what this means depending on wind direction and time of day. On my visit I got to watch planes queuing up to depart - almost ten of them at one point - then lining themselves up at the end of the runway and preparing for the off. A whine of engine, then a roar, and a succession of aircraft launched off on the first mile of their long haul, generally taking off just out of sight behind the Cargo Centre. The Boeing double deckers were the loudest, with a visceral scream, while the best view was of an Aeroflot A330 taxiing almost directly behind the fence. I stood with a handful of spotters parked up at the lone Esso garage, and enjoyed.
A bit further along the road the view is again blocked by an undulating concrete barrier, this to shield passing traffic from the Glidepath Critical Area. At the final roundabout the two artificial rivers dip briefly underground, part of the relandscaping of the area in 2004 to accommodate Terminal 5, which is now rapidly approaching. One of the best views comes through the mesh where the Western Perimeter Road begins, immediately adjacent to the run of red poles supporting the lights marking the end of the runway. The lampposts are lower here so as not to intrude into protected airspace, clearly distinguishing the stretch of road beneath the actual flightpath. I was fortunate enough to be here when an A380 came into land, great hulking beast that it is, but had operations been running in the opposite direction I could have seen a heck of a lot more aerial action.
Terminal 5, thankfully, is a lot easier to walk into than Terminal 4 was to walk out of. The bus station connects at ground level, beneath one great curving overpass which brings arrivals traffic down from above. Should you be planning on making the walk in the opposite direction (from T5 to T4), head for the illuminated 3-letter-code airport artwork outside the south end of the terminal, head to the right past the bike rack and you'll soon be on the perimeter road. Of course there's no need whatsoever to walk - buses run regularly between T5 and T4, and they're free because they lie inside the Heathrow Free Travel Zone. The same goes for the tube, and the Heathrow Express, so only a fool would ever choose to walk the four miles inbetween instead. I'm glad to have been that fool, if only for the planespotting opportunities, and a better insight into what makes Europe's busiest airport tick.